Flashcards in Antifungals Deck (22)
How does the -azole group work?
Inhibit C14 alpha demethylase needed for cell membrane ergosterol synthesis by fungi (ie acts in the ER)
Posaconazole kills zygomycetes AND IS SUPERIOR COMPARED WITH FLUCONAZOLE FOR PROPHYLAXIS AGAINST INVASIVE FUNGAL INFECTIONS IN HIGH RISK PATIENTS. Does not kill Sporothrix
Voriconazole side effect?
Transient visual disturbance
Asymptomatic hepatic enzymes up
Good for Aspergillus, candida, scedosporium, fusarium
Amphotericin B mechanism? (polyene)
Inserts into cell membrane which increases permeability and all the potassium and intracellular components leak out
Aspergillus, Candida except lusitaniae
Covers glabrata and krusei
Can treat zygomycosis and fusariosis
Note that Nystatin are polyenes
Why do you give lipophilic ambisome?
Less nephrotoxic and greater CNS penetration
Works by liposome preferentially binding fungal cell wall and amphotericin B released to bind ergosterols in the cell membrane forming pores.
Decreases GFR, direct vasoconstriction of afferent arterioles
K, Mg, HCO3 wasting
How do echinocandins work?
eg Anidulafungin, Micafungin, Caspofungin (empiric therapy in feb/neut, treat candida infections)
Inhibit glucan synthase which is needed for production of beta 1,3 glucan in fungal cell walls
Cover candida and aspergillosis but not cryptococcus or non-aspergillus moulds
Deaminated to 5-FU-->inhibitor of thymidylate synthetase (DNA synthesis)
Work against candida and in combination with Amphotericin for cryptococcus
Alemtuzumab incrases rate of which infections?
Ab against CD52
used in CLL or cutaneous T cell lumphoma
Increases mould infections, CMV, PCP
What causes PML?
Humanised monoclonal antibody against alpha 4 integrin
Splenectomy when can you vaccinate?
Vaccinate pre-operatively or 2 weeks post op
When can you re-vaccinate following BMT?
6 months post auto
12 months post allo
What is the best marker of risk of transmission of HBV after occupational exposure?
HBeAg status of source
Risk actually quite high- 30-50%
Inhibit fungal ergosterol synthesis at an earlier stage than the azoles
Most candida except glabrata and krusei (dose dependent)
Could use for candidaemia in non neutropaenic and haemodynamically stable patients
NO mould activity
Does cover cryptococcus so need to give after the 5FC/ambisome finished
Fluconazole + aspergillus + histoplasmosis
Candida including Krusei
Fusarium (unlike ambisome)
Scedosporium (unlike ambisome)
As vori + zygomycetes
Only oral admin
BETTER THAN fluconazole for prophylaxis in terms of mortality rate
NOT any non aspergillus moulds
Used in treatment of IC in neutropaenic patients and in C glabrata infection
Candidaemia treatment options...
If immunocompetent, fluconazole, voriconazole, ambisome, capsofungin,
If neutropaenic, capsofungin or liposomal amphotericin B
Voriconazole first line
Reverse underlying condition
High dose amphotericin B
Followed by posaconazole as sequential
Which ones get drug level monitoring?